If you’re anything like us, you’re probably enjoying a snack while checking your email and catching up on your blogs. If you’re eating a conventionally produced snack – that is, one that is not Certified Organic or Non-GMO Verified – chances are it could be full of GMOs. Check your packaging. Did you see the label informing you of this fact? Most likely you didn’t because companies are not required to tell you whether or not GMOs are in your foods. And yet, GMOs are in about 80% of commonly processed foods. So what are GMOs and what is their impact on human and animal health and the environment?

Genetically Modified Organisms (GMOs) are organisms whose genetic material has been altered using genetic engineering techniques. Such genetic engineering techniques include laboratory-induced DNA alteration or adding or subtracting from the organism’s genome. According to the USDA, genetically modified (GM) plants are created to “provide protection from or resistance to environmental threats, to modify the quality of agricultural products, to increase the nutritional value of foods, and to accelerate the growth of the organism.” However, a growing body of scientists, researchers, agriculturists and consumer advocates are questioning if indeed genetically engineered foods are fulfilling those promises or if indeed they are creating their own potential health and environmental crisis.

What Crops are Genetically Engineered, or GMO?

There are nine genetically engineered crops currently approved for commercial production in the United States market. They include:

• Corn • Cotton • Hawaiian Papaya • Soybeans • Sugar Beets

• Zucchini • Canola • Alfalfa • Yellow Crookneck Squash

The five major varieties—soy, corn, canola, cotton, and sugar beets—have bacterial genes inserted, which allow the plants to survive an otherwise deadly dose of weed killer. The second GM trait is a built-in pesticide, found in GM corn and cotton.

GMOs, Human Health and the Environment

Potential Human Risks:

There are a variety of scientific studies citing allergic reactions, liver problems, reproductive dysfunctions, and epidemics stemming from the consumptions of GM or genetically modified foods. Tests of GMOs on laboratory rats is a first step to extrapolate their dangers on humans. A 2005 report in the journal Allergy and Asthma Proceedings revealed that a skin prick allergy test showed that some people react to genetically modified soy, but not to wild natural soy. A gene called Bt (for Bacillus thuringiensis) is inserted into the plant’s DNA, where it secretes the insect-killing Bt-toxin in every cell. This is found primarily in GM corn and cotton. A study has shown that mice that were fed the Bt-toxin started having immune reactions to formerly harmless foods. This means that, after the introduction of Bt, these animals developed allergies to non-GMO foods. Lab rats have also experienced reproductive issues after being introduced to GMs. A study conducted by Institute of Higher Nervous Activity and Neurophysiology of the Russian Academy of Sciences (RAS) found that more than half of the babies of mother rats fed GM soy died within three weeks. Additionally, there is anecdotal evidence of death of animals after grazing on Bt cotton plants after they were harvested. Farmers in India report that thousands of sheep, buffalo, and goats have died as a result of eating GM crops.

Documented Human Risks:

To date there have been no human clinical trials of GM foods. Pro-GMO groups state, “[It is] generally agreed that long-term monitoring of the human health risks of GM food through epidemiological studies is not necessary because there is no scientific evidence suggesting any long-term harm from these foods.” However, in 2004, the journal Nature Biotechnology published the results of a study of a human GM feeding experiment that revealed that the genetic material inserted into GM soy transfers into bacteria living inside human intestines and continues to function. According to the Institute for Responsible Technology, this means that humans may still have GM proteins produced continuously inside them. These may be proteins altered in a way the human body doesn’t recognize and may be contributing to an increase in food allergies.

GM food supplements have caused human deaths in the past. In the late 1980s, a contaminated brand of a food supplement called L-tryptophan killed about 100 Americans and caused sickness and disability in another 5,000-10,000 people. The source of contaminants was almost certainly the genetic engineering process used in its production. As there is currently no monitoring for GMO-related illnesses and no long-term animal studies, there is an inability to identify the source of the problem.

Environmental Risks:

Many genetically modified crops are altered to be resistant to herbicides and pesticides. In many cases, farmers have been known to overuse herbicides and pesticides, as they do not harm the crop. Nature published a study that showed that pollen from Bt corn resulted in a high mortality rate among monarch butterfly caterpillars. The caterpillars feed on milkweed plants but the pollen from the Bt corn from a neighboring field interacted with the milkweed plants. The caterpillars would consume this infected milkweed and die. The potential risk posed to non-target organisms is a real concern. Additionally, the United States Geological Survey (USGS) has found the herbicide glyphosate (Roundup) consistently in rain, rivers, surface water and air throughout the entire growing season in agricultural areas in the Mississippi River watershed.

“Super Weeds”

As weeds adapt to herbicides, they develop resistance and evolve into what are called “super weeds.” When that happens, herbicide use increases and the benefits of herbicide resistant crops are diminished, if not lost. This is a counterintuitive finding, as one would assume that crops that are engineered to resist herbicides should result in the decrease in the use of herbicides. However, as Washington State University research professor Charles Benbrook found in his research, herbicide-tolerant crops worked extremely well in the first few years of use, but the weeds became resistant to the herbicides being used causing farmers to use increasing amounts weed killing chemicals to try to control these “super weeds.”

A 2011 Dow Chemical Co. study found as many as 20 million acres of GMO corn and soybeans may be infested with Roundup-resistant “super weeds.” Farmers spend more money to buy herbicide resistant seeds to plant. However, now that weeds are resistant to the herbicide as well, farmers are using older herbicides like 2,4-D that many have deemed to be dangerous to humans and has been shown to cause birth defects in animals exposed to the chemical. Before the introduction of these herbicide resistant plants, farmers used “multiple herbicides, which slowed the development of resistance. They also controlled weeds through plowing and tilling — practices that deplete topsoil and release carbon dioxide, but do not encourage resistance. The GM crops allowed growers to rely almost entirely on glyphosate, which is less toxic than many other chemicals and kills a broad range of weeds without plowing. Farmers planted them year after year without rotating crop types or varying chemicals to deter resistance.”

Counterpoints from the Bioscience Community

The corporations developing GM crops object to the claims that GMOs are harmful to humans and the environment. On its website, Monsanto states of its genetically modified foods, “so long as the introduced protein is determined safe, food from GM crops determined to be substantially equivalent is not expected to pose any health risks. Further, it is impossible to design a long-term safety test in humans, which would require, for example, intake of large amounts of a particular GM product over a very large portion of the human life span. There is simply no practical way to learn anything via human studies of whole foods. This is why no existing food – conventional or GM – or food ingredient/additive has been subjected to this type of testing.”

In general, companies that produce genetically modified organisms argue that there is no evidence to prove that GMOs are harmful. Organizations like the American Association for the Advancement of Science (AAAS) state that GM crops “pose no greater risk than the same foods made from crops modified by conventional plant breeding techniques.” This statement, however, was refuted by the Center for Responsible Genetics (CRG), claiming that the AAAS came to this decision without vote by its full membership and without a complete review of the science behind the statement. Further, the American Academy of Environmental Medicine called for a moratorium on genetically modified (GM) foods, stating: “Avoid GM foods when possible… Several animal studies indicate serious health risks associated with GM food… There is more than a casual association between GM foods and adverse health effects. There is causation… The strength of association and consistency between GM foods and disease is confirmed in several animal studies.”

The overarching position from companies with a financial stake in the production of GMOs is that there is no evidence to prove that GMOs are harmful, therefore, the public should not worry about any real or perceived health threat from GMOs, and that mandatory labeling of GMOs would only “confuse the consumer.”

Consumers React

The risk of GMOs being harmful to humans and the environment has mobilized efforts around the world. In the US, several states have tried to tackle the GMO issue. Most notable are the efforts put forth in California. California Proposition 37 was written with input from food groups, industry, science, and legal and health experts. The initiative was designed to require clear labeling to let consumers know if their food was genetically modified. Corporations like Monsanto and DuPont spent millions of dollars to defeat the initiative, arguing that a food-labeling requirement would cause foods to be banned for sale unless they were repackaged, relabeled or remade with higher cost ingredients, therefore increasing food costs for consumers. Proposition 37 was presented to California voters in November 2012 and was defeated in a very close vote. Despite the loss, the awareness of this issue has encouraged other action like Initiative 522, which will be presented to Washington State voters in November 2013.

On May 25, 2013, more than 2 million people in 50 countries worldwide marched to protest Monsanto and bring public awareness to genetically modified foods. This grassroots protest was organized in February 2013 and quickly grew into a worldwide event. There is increasing public support for the labeling of GMO products. Although there have been setbacks in the movement, there is increasing public support for labeling.

What You Can Do

There are a number of things you can do to learn more about genetically engineered foods and to support the consumer’s right to know how our food is produced.

First, in order to ensure that you are not eating GMOs, choose organic. Foods that bear the USDA organic seal are prohibited from using GMOs in organic production.

Next, consumers should support labeling of products containing GMOs. Groups like the Non-GMO Project have a verification seal for products that contain no GMOs. Just Label It supports the labeling of products that contain GMOs.

Regardless of whether you live in the state of Washington or not, citizen consumers can support the efforts of the Yes on 522 Initiative. This Washington initiative will be before voters in November 2013 and seeks to require labeling on foods that contain GMOs. If the state initiative passes, it will change the debate on mandatory federal labeling of GMOs in the U.S.

Last, consumers are encouraged to join social media efforts like GMO Inside which gives people information and tools, and provides a place for a growing community of people from all walks of life to share information and actions around genetically engineered foods.

Currently about 93% of the US population supports labeling of GMOs. However, the influence and dollars from large corporations are preventing consumers from having a clear understanding of whether or not GMOs are in their food. These grassroots efforts by organizations and concerned citizens is the best way to change the conversation and encourage companies to provide transparency to the public by clearly stating which products contain GMOs.